Comprehensive pharmacogenetic profiling of advanced colorectal cancer.

3509 Background: Inherited genetic factors may influence a patient’s response to, and side effects from, chemotherapy and biological therapies. Here, we sought to generate a comprehensive inherited pharmacogenetic profile for advanced colorectal cancer (aCRC). Methods: We analysed 260 potentially functional coding region and promoter variants in genes within the 5-FU, capecitabine, oxaliplatin, EGFR and DNA repair pathways in 2183 patients with aCRC treated with oxaliplatin-fluoropyrimidine chemotherapy ± cetuximab (from the MRC COIN and COIN-B trials). Primary outcomes assessed were 12-week response, skin rash (SR) (for those receiving cetuximab), dose-reduction or delay in treatment due to any toxicity and peripheral neuropathy (PN). Results: For variants with minor allele frequencies >20%, we had >85% power to detect an effect on response / toxicity with an OR of 1.3. In patients treated with chemotherapy + cetuximab, 5 and 4 coding region variants in the EGFR pathway were associated with response and ...